Embedded Design Handbook

ID 683689
Date 8/28/2023
Public
Document Table of Contents

3.5.1.2. Non-Volatile Memory

Non-volatile memories retain their contents when power is switched off, making them good choices for storing information that must be retrieved after a system power-cycle. Processor boot-code, persistent application settings, and FPGA configuration data are typically stored in non-volatile memory. Although non-volatile memory has the advantage of retaining its data when power is removed, it is typically much slower to write to than volatile memory, and often has more complex writing and erasing procedures. Non-volatile memory is also usually only guaranteed to be erasable a given number of times, after which it may fail. Examples of non-volatile memories include all types of flash, EPROM, and EEPROM. Most modern embedded systems use some type of flash memory for non-volatile storage.

Many embedded applications require both volatile and non-volatile memories because the two memory types serve unique and exclusive purposes. The following sections discuss the use of specific types of memory in embedded systems.